Chemistry - Electrochemistry Question with Solution | TestHub

The given reaction is the reduction of zinc:

${\mathrm{Zn}}_{(aq)}^{2+}+2e^{-}\to {\mathrm{Zn}}_{(s)}$ with $E^{\circ }=-0.76\text{ V}$

The required reaction is the oxidation of zinc:

$2{\mathrm{Zn}}_{(s)}\to 2{\mathrm{Zn}}_{(aq)}^{2+}+4e^{-}$

This reaction is obtained by reversing the given reduction reaction and multiplying it by 2. Reversing a cell reaction changes the sign of its standard potential. Therefore, the standard oxidation potential is:

$E_{\text{ox}}^{\circ }=-E_{\text{red}}^{\circ }=-(-0.76\text{ V})=+0.76\text{ V}$

Multiplying the reaction by a stoichiometric coefficient does not change the value of the standard potential because standard electrode potential is an intensive property. It depends only on the nature of the material and the concentration, not on the amount of substance reacting.

Thus, the standard potential for the given reaction remains $+0.76\text{ V}$.

Answer: $+0.76\mathrm{V}$